Bug 1223376

Summary: not enough MMIO resources for SR-IOV
Product: Red Hat Enterprise Linux 7 Reporter: Alona Kaplan <alkaplan>
Component: kernelAssignee: Stefan Assmann <sassmann>
kernel sub component: NIC Drivers QA Contact: zenghui.shi <zshi>
Status: CLOSED CANTFIX Docs Contact:
Severity: high    
Priority: high CC: alkaplan, alonbl, bazulay, danken, ibarkan, jpirko, juzhou, kzhang, network-qe, tgraf, yanghliu
Version: 7.1   
Target Milestone: rc   
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2015-05-27 10:16:32 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Attachments:
Description Flags
lspci --vvv (output for enp2s0f0)
none
lspci --vvv (output for enp2s0f1)
none
modinfo igb
none
dmesg none

Description Alona Kaplan 2015-05-20 12:23:25 UTC
Created attachment 1027699 [details]
lspci --vvv (output for enp2s0f0)

Description of problem:
The host has two SR-IOV nics- enp2s0f0 and enp2s0f1.
enp2s0f0 works fine.
However, when trying to configure VFs on enp2s0f1 the following error is thrown- kernel: igb 0000:02:00.1: not enough MMIO resources for SR-IOV.

Version-Release number of selected component (if applicable):


How reproducible:
100%

Steps to Reproduce:
1. ssh root.16.144
2. echo 1 > /sys/class/net/enp2s0f1/device/sriov_numvfs

Actual results:
-bash: echo: write error: Cannot allocate memory

journalctl output-
May 20 12:41:02 nari04.eng.lab.tlv.redhat.com kernel: igb 0000:02:00.1: not enough MMIO resources for SR-IOV



Expected results:
Succeed creating VFs on enp2s0f1.

Additional info:
The host's ip- nari04.eng.lab.tlv.redhat.com (10.35.16.144).
Kernel version- 3.10.0-229.4.2.el7.x86_64
sriov driver- igb (version- 5.2.13-k)
Ethernet controller- Intel Corporation 82576 Gigabit Network Connection (rev 01)

Comment 1 Alona Kaplan 2015-05-20 12:24:19 UTC
Created attachment 1027700 [details]
lspci --vvv (output for enp2s0f1)

Comment 2 Alona Kaplan 2015-05-20 12:26:45 UTC
Created attachment 1027703 [details]
modinfo igb

Comment 4 Alon Bar-Lev 2015-05-20 12:51:35 UTC
The non operational (second) card has:
---
        Capabilities: [160 v1] Single Root I/O Virtualization (SR-IOV)
                IOVCap: Migration-, Interrupt Message Number: 000
                IOVCtl: Enable- Migration- Interrupt- MSE- ARIHierarchy-
                IOVSta: Migration-
                Initial VFs: 8, Total VFs: 8, Number of VFs: 0, Function Dependency Link: 01
                VF offset: 128, stride: 2, Device ID: 10ca
                Supported Page Size: 00000553, System Page Size: 00000001
                Region 0: Memory at 0000000000000000 (64-bit, non-prefetchable)
                Region 3: Memory at 0000000000000000 (64-bit, non-prefetchable)
                VF Migration: offset: 00000000, BIR: 0
---

Notice the 0 at regions.
This happens at two different machines, it is not specific to a single configuration.
Kernel command-line includes intel_iommu=on.

Comment 5 Alona Kaplan 2015-05-20 12:56:18 UTC
Alon tried to reproduce the issue using vanilla kernel (3.18.12). It seems to be even worse, it was impossible to create VFs on both of the nics (both of them had 0 at regions).

Comment 6 Stefan Assmann 2015-05-27 07:30:45 UTC
A full dmesg output would be helpful. Meanwhile try the following kernel cmdline options one after another.
pci=assign-busses
pci=realloc

Comment 7 Alona Kaplan 2015-05-27 08:52:17 UTC
Created attachment 1030426 [details]
dmesg

Comment 8 Stefan Assmann 2015-05-27 09:03:10 UTC
pci=nocrs would be another kernel cmdline option to try.

Comment 9 Stefan Assmann 2015-05-27 10:16:32 UTC
Not enough MMIO resources is a BIOS issue, so you might check if there's a newer BIOS available. If none of the suggested workarounds help you're pretty much out of luck.
There's been a similar case, discussed in bug #723583.

Going to close this as CANTFIX, as it is a BIOS issue and possible workarounds have been listed.

Comment 10 Alona Kaplan 2015-05-28 05:47:28 UTC
pci=realloc solved the issue. Thanks.